1. Inoue, M., in Sub-arcsecond Radio Astronomy, ed. R. J. Davis and R. S. Booth. Cambridge: Cambridge University Press, 1993, p. 434
2. Kardashev, N. S. and Slysh, V. I., in The Impact of VLBI on Astrophysics and Geophysics, ed. M. J. Reid and J. M. Moran. Kluwer Academic, 1988, p. 433
3. Ulvestad, J., Planning for future Space VLBI missions, Summary of Meeting held at JPL, 8 March, 1994
4. Tsarevski, G., in The Problem of Search for Life in the Universe. Moscow: Nauka, in Russian, 1986, p. 183
5. Maccone, C., SETI investigations by the Quasat Radioastronomy Satellite IAA-87-590 paper, 1987